Answer:
See explanation below
Explanation:
The melting point (the temperature that it changes from solid to liquid) of a pure substance depends on its mass, the forces between its molecules, and the pressure of the system.
The melting point, or the freezing point, of a mixture, is a temperature between the melting point of its components. Salt has a huge negative melting point, so when it is added to the water, the melting point decreases from 0ºC to -21ºC approximately.
So, the water will only freeze again if the temperature becomes below -21ºC which is very difficult to happen.
C.silicon and oxygen is the answer
Answer: pH = 4.996
Explanation:
No of moles = molarity x volume
:• no of moles of CH3COOH = 0.1M x 0.1L
n(CH3COOH) = 0.1mol
Since 0.03mole of NaOH is added, then 0.03 mole of CH3COOH will be converted to the conjugate.
Therefore, Moles of CH3COOH becomes,
0.1 - 0.03 = 0.07 mol
Subsequently, the moles of CH3COONa increases and becomes,
0.08 + 0.03 = 0.11 mol
Using the Hendersom-Hasselbach equation,
pH = pKa + log [Moles of conjugate÷ moles of Ch3COOH]
From literature, pKa of Ch3COOH is 4.8
Thus,
pH = 4.8 + log [0.11/0.07]
pH = 4.8 + 0.1963
pH = 4.996
